Fine Motion Strategies for Robotic Peg-Hole Insertion

The robotic assembly operation has a prominent role in industry due to the fact that (a) it accounts for a substantial proportion of production cycle times and (b) it requires high precision. The peg-hole insertion operation, which is a simplified industrial application model, has special prominence. In terms of the hardware, various complex six-component force sensors, passive compliance and vibration systems have been designed for this purpose alone. In the control area, the disturbance filter and real-time control have been applied to the system to enhance performance. Techniques using geometric concepts such as pre-images and back-projections, models of the contact configurations, pattern recognition and fine motion analysis have been studied. The objective of this paper is to illustrate a method that combines these ideas together to solve practical problems. In this paper: 1. General contact configurations and contact motions between the peg and hole are presented. 2. An important problem in the identification of the contact configuration according to the force sensors is studied. It is concluded that the complete identification of the contact configuration should depend not only on the signals from the force sensors but also on the knowledge about the range of the initial state of the peg and clever utilization of the environment. 3. Various strategies with and without force sensors are proposed. Motion and model analysis is used to study the general identification and motion problems in the peg-hole insertion system. Pre-image and back-projection concepts are employed to enable practical implementation of the method which used Petri nets. Selecting the configuration parameters that can be (a) easily measured and (b) used to decide the incremental motion steps through the procedure were found to be complex and critical tasks that enabled success. These strategies have been verified through experimental trials. It is apparent that the fine motion strategy has a wide application in the robotic peg-hole insertion operation.

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Innovative Strategy to Improve Precision and to Save Power of a Real-Time Control Process Using an Online Adaptive Fuzzy Logic Controller

Advances in Fuzzy Systems ◽

10.1155/2013/658145 ◽

2013 ◽

Vol 2013 ◽

pp. 1-16 ◽

Cited By ~ 2

Author(s):

R. Lasri ◽

I. Rojas ◽

H. Pomares ◽

O. Valenzuela

Keyword(s):

Fuzzy Logic ◽

Real Time ◽

Fuzzy Logic Controller ◽

Control Process ◽

Control Area ◽

Real Time Control ◽

Innovative Strategy ◽

Adaptive Fuzzy ◽

Time Control ◽

Adaptive Fuzzy Logic

The main objective of this paper is to prove the great advantage that brings our novel approach to the intelligent control area. A set of various types of intelligent controllers have been designed to control the temperature of a room in a real-time control process in order to compare the obtained results with each other. Through a training board that allows us to control the temperature, all the used algorithms should present their best performances in this control process; therefore, our self-organized and online adaptive fuzzy logic controller (FLC) will be required to present great improvements in the control task and a real high control performance. Simulation results can show clearly that the new approach presented and tested in this work is very efficient. Thus, our adaptive and self-organizing FLC presents the best accuracy compared with the remaining used controllers, and, besides that, it can guarantee an important reduction of the power consumption during the control process.

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Application of a computer-based approach to designing real-time control software for an integrated robotic assembly and automated storage/retrieval system†

International Journal of Production Research ◽

10.1080/00207548808947972 ◽

1988 ◽

Vol 26 (10) ◽

pp. 1593-1604 ◽

Cited By ~ 6

Author(s):

W. ROBERT TERRY ◽

HARISH G. RAO ◽

JU Y. SON

Keyword(s):

Real Time ◽

Retrieval System ◽

Robotic Assembly ◽

Real Time Control ◽

Control Software ◽

Time Control ◽

Computer Based ◽

Automated Storage

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A nonparametric approach using artificial intelligence in vibration and noise reduction of flexible systems

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406213508510 ◽

2013 ◽

Vol 228 (8) ◽

pp. 1329-1347 ◽

Cited By ~ 10

Author(s):

Ali Zolfagharian ◽

Amin Noshadi ◽

Seyed Ebrahim Ghasemi ◽

Mohd Zarhamdy Md Zain

Keyword(s):

Artificial Intelligence ◽

High Speed ◽

Fuzzy Controller ◽

Nonlinear System Identification ◽

Control Area ◽

Real Time Control ◽

Elman Neural Network ◽

Noise And Vibration ◽

Nonparametric Approach ◽

Time Control

The main aim of this paper is to broaden the application’s area of artificial intelligence including fuzzy logic and multiobjective evolutionary algorithm into real-time control area. Wiper system is a high order, nonlinear model with single-input and multi-outputs so that rise time, maximum overshoot, and end-point vibration of wiper blade are observed in conflict as the faster response leads to the larger level of undesired noise and vibration. The first part of this paper centers acquiring experimental data from a passenger automobile wiper system during its operation and using a reliable nonlinear system identification, namely, nonlinear autoregressive exogenous Elman neural network. Knowing that in a practical environment, where the loading conditions of the flexible wiper blade may be varied due to rain, snow, or wind lift in high-speed driving, causing changes in the characteristics of the system, the system performance with a fixed conventional controller scheme will not be satisfactory. The main contribution of this work is presented in second part where a novel multiobjective, bilevel adaptive-fuzzy controller is proposed for an automobile wiper system. The system’s parameters are tuned simultaneously by a multiobjective genetic algorithm based on fitness sharing whereby an automobile wiper blade is moved within its sweep workspace in the least amount of time with minimum noise and vibration.

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Improvement of a recirculating plant by introducing star control

Water Science & Technology ◽

10.2166/wst.1995.0096 ◽

1995 ◽

Vol 31 (2) ◽

pp. 171-180 ◽

Cited By ~ 5

Author(s):

Marinus K. Nielsen ◽

Tine B. Önnerth

Keyword(s):

Wastewater Treatment ◽

Real Time ◽

Wastewater Treatment Plants ◽

Control Strategies ◽

Biological Nutrient Removal ◽

Practical Implementation ◽

Real Time Control ◽

Dynamic Identification ◽

Time Control ◽

On Line

During the last 20 years, control of wastewater treatment plants has developed from very simple to advanced computer control methods based on on-line measurements. Fortunately, both on-line equipment and computer system technology are still developing fast and have become applicable at WWTPs. The use of on-line measurements for real time control is advantageous at most plants over 15.000 personal equivalent performing biological nutrient removal. Control strategies have demonstrated their efficiency at several Scandinavian wastewater treatment plants. Experience shows that the applied control strategies are efficient and robust for practical implementation, provide savings in energy and chemical consumption and decreases the nitrogen content in the effluent. Experience from a recirculating BNR plant using the STAR concept for advanced real time control is described. The on-line nutrient measurements and excitation of the processes through control strategies have improved the process understanding. Control has reduced the consumption of energy by about 30% and eliminated the need for external carbon addition, as well as improved the effluent quality of total nitrogen from the plant. The new measurements and data handling methods will make it possible to perform dynamic identification of activity in recirculating plants (Nielsen et.al., 1994), and hence give information as to which control strategies improve the biomass activity or favour desired cultures of micro-organisms.

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A Real Time Control Architecture for Continuously Managing Patients in a Care Unit

Methods of Information in Medicine ◽

10.1055/s-0038-1634619 ◽

1995 ◽

Vol 34 (05) ◽

pp. 475-488

Author(s):

B. Seroussi ◽

J. F. Boisvieux ◽

V. Morice

Keyword(s):

Real Time ◽

Linear Time ◽

Treatment Plan ◽

Control Architecture ◽

Real Time Control ◽

Time Representation ◽

Time Control ◽

Continuous Support ◽

Definition Of ◽

Computerized System

Abstract:The monitoring and treatment of patients in a care unit is a complex task in which even the most experienced clinicians can make errors. A hemato-oncology department in which patients undergo chemotherapy asked for a computerized system able to provide intelligent and continuous support in this task. One issue in building such a system is the definition of a control architecture able to manage, in real time, a treatment plan containing prescriptions and protocols in which temporal constraints are expressed in various ways, that is, which supervises the treatment, including controlling the timely execution of prescriptions and suggesting modifications to the plan according to the patient’s evolving condition. The system to solve these issues, called SEPIA, has to manage the dynamic, processes involved in patient care. Its role is to generate, in real time, commands for the patient’s care (execution of tests, administration of drugs) from a plan, and to monitor the patient’s state so that it may propose actions updating the plan. The necessity of an explicit time representation is shown. We propose using a linear time structure towards the past, with precise and absolute dates, open towards the future, and with imprecise and relative dates. Temporal relative scales are introduced to facilitate knowledge representation and access.

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